The direction for this unit is toward elucidating the mechanisms for control of protein synthesis and applying them to therapy of cancer and AIDS. Three areas of investigation include l) understanding the multiple lesions produced in mammalian cells by amino acid deprivation 2) determining the mechanism of action of sulfhydryl growth factors for human tumor cells in primary culture. The information has been applied to anti- cancer drug design and synthesis and patents obtained. 3) Utilizing selective amino acid antagonists to block the processing of retrovirus polyprotein as a target in the therapy of AIDS.